Ultrafiltration in Japanese critically ill patients with acute kidney injury on renal replacement therapy

A recent worldwide survey indicates an international diversity in net ultrafiltration (UFNET) practices for the treatment of fluid overload in critically ill patients with acute kidney injury (AKI) requiring renal replacement therapy (RRT). The sub-analysis of the survey has demonstrated that maximum doses of furosemide used before determination of diuretic resistance are lower in Japan than those prescribed worldwide and UFNET is lower but is initiated earlier. In contrast, the interval during which practitioners evaluate fluid balance is longer. The characterization of RRT in critically ill patients in Japan should unveil more appropriate approaches to the successful treatment of AKI.

Prognostic impact of uric acid in patients with acute decompensated heart failure

Aim. To evaluate the prognostic impact of serum uric acid (SUA) on clinical outcomes in patients with acute decompensated heart failure, as well as identify the correlation between hyperuricemia and renal function and diuretic resistance in these patients. Materials and methods. The study included 175 patients (125 men and 50 women) with NYHA class IIIV acute decompensated heart failure. Median age was 64 (5675) years. The Information regarding the survival was obtained 3 years after the admission by telephone calls. Results. 57 patients reached the end point (death from all causes); therefore, all patients were divided into groups: "alive", "dead". The SUA levels did not differ in the groups. The only significant difference in the studied parameters was the estimated glomerular filtration rate (eGFR), which was significantly higher in the "alive" group [70.5 (52.894) and 56 (4079), respectively; p=0.006]. A moderate negative correlation was found between SUA levels and eGFR in the correlation analysis (r=-0.313, p0.001). A comparative analysis showed, that SUA level on admission was significantly higher in patients who subsequently received increased doses of diuretics than in patients with a satisfactory response to standard doses of diuretics [567.8 (479.6791.9) and 512 (422.4619.4), respectively; p=0.011]. Also, higher eGFR level on admission was observed in patients from the normal SUA level group than in patients from the hyperuricemia group [94 (74.5101.5) and 63 (48.881.3), respectively; p=0.002]. Conclusion. We found no significant differences in the uric acid level in patients who reached the end point and those who did not reach it during the three-year follow-up. However, the found correlation between uric acid levels and diuretic resistance calls for further research.

Diuretic Resistance Treated with Low-Dose Hydralazine: A Case Report and Review of the Literature

We present a case of severe diuretic resistance and edema from acute cardiorenal syndrome complicating heart failure with preserved ejection fraction (HFpEF) and mild alcoholic liver disease. High doses of intravenous (iv) furosemide plus iv doses of chlorothiazide failed to increase the daily urine output (UV) above 1,500 mL or the fractional excretion of sodium (FE_Na) above 2%. The addition of a relatively low dose of hydralazine (10 mg thrice daily PO) during 5 days of constant iv infusion of furosemide plus iv bolus chlorothiazide doubled the UV and FE_Na while reducing the serum creatinine concentration from 3.3 to 2.0 mg/dL. Hydralazine may have restored a response to the diuretics by increasing the renal blood flow and thereby the renal diuretic delivery, or by reducing the filtration fraction or reducing the renal congestion and thereby reducing the proximal reabsorption during blockade of distal reabsorption with diuretics. Further mechanistic studies of low-dose hydralazine for diuretic resistance are warranted.

Improving Diuretic Response in Heart Failure by Implementing a Patient-Tailored Variability and Chronotherapy-Guided Algorithm

Heart failure is a major public health problem, which is associated with significant mortality, morbidity, and healthcare expenditures. A substantial amount of the morbidity is attributed to volume overload, for which loop diuretics are a mandatory treatment. However, the variability in response to diuretics and development of diuretic resistance adversely affect the clinical outcomes. Morevoer, there exists a marked intra- and inter-patient variability in response to diuretics that affects the clinical course and related adverse outcomes. In the present article, we review the mechanisms underlying the development of diuretic resistance. The role of the autonomic nervous system and chronobiology in the pathogenesis of congestive heart failure and response to therapy are also discussed. Establishing a novel model for overcoming diuretic resistance is presented based on a patient-tailored variability and chronotherapy-guided machine learning algorithm that comprises clinical, laboratory, and sensor-derived inputs, including inputs from pulmonary artery measurements. Inter- and intra-patient signatures of variabilities, alterations of biological clock, and autonomic nervous system responses are embedded into the algorithm; thus, it may enable a tailored dose regimen in a continuous manner that accommodates the highly dynamic complex system.

A systematic review of the evidence supporting post-operative diuretic use following cardiopulmonary bypass in children with Congenital Heart Disease

Background: Paediatric cardiac surgery on cardiopulmonary bypass induces substantial physiologic changes that contribute to post-operative morbidity and mortality. Fluid overload and oedema are prevalent complications, routinely treated with diuretics. The optimal diuretic choice, timing of initiation, dose, and interval remain largely unknown. Methods: To guide clinical practice and future studies, we used PubMed and EMBASE to systematically review the existing literature of clinical trials involving diuretics following cardiac surgery from 2000 to 2020 in children aged 0–18 years. Studies were assessed by two reviewers to ensure that they met eligibility criteria. Results: We identified nine studies of 430 children across four medication classes. Five studies were retrospective, and four were prospective, two of which included randomisation. All were single centre. There were five primary endpoints – urine output, acute kidney injury, fluid balance, change in serum bicarbonate level, and required dose of diuretic. Included studies showed early post-operative diuretic resistance, suggesting higher initial doses. Two studies of ethacrynic acid showed increased urine output and lower diuretic requirement compared to furosemide. Children receiving peritoneal dialysis were less likely to develop fluid overload than those receiving furosemide. Chlorothiazide, acetazolamide, and tolvaptan demonstrated potential benefit as adjuncts to traditional diuretic regimens. Conclusions: Early diuretic resistance is seen in children following cardiopulmonary bypass. Ethacrynic acid appears superior to furosemide. Adjunct diuretic therapies may provide additional benefit. Study populations were heterogeneous and endpoints varied. Standardised, validated endpoints and pragmatic trial designs may allow investigators to determine the optimal diuretic, timing of initiation, dose, and interval to improve post-operative outcomes.